CHAPTER II.
THE PROCESS OF LIFE.
| Illustration from respiration | [21] |
| Illustration from nutrition | [25] |
| The utilization of the materials incorporated | [27] |
| The analogy of a gas-engine. Explosive metabolism | [30] |
CHAPTER III.
REPRODUCTION AND DEVELOPMENT.
| Reproduction in the protozoa | [37] |
| Fission in the metazoa | [41] |
| The regeneration of lost parts | [41] |
| Reproduction by budding | [42] |
| Sexual reproduction | [42] |
| Illustration of development | [51] |
| Parental sacrifice | [56] |
| The law of increase | [58] |
CHAPTER IV.
VARIATION AND NATURAL SELECTION.
| The law of persistence | [61] |
| The occurrence of variations | [63] |
| Application of the law of increase | [76] |
| Natural selection | [77] |
| Elimination and selection | [79] |
| Modes of natural elimination illustrated | [80] |
| Protective resemblance and mimicry | [82] |
| Selection proper illustrated | [93] |
| The effects of natural selection | [95] |
| Isolation or segregation | [99] |
| Its modes, geographical, preferential and physiological | [99] |
| Its effects | [108] |
| Utility of specific characters | [110] |
| Variations in the intensity of the struggle for existence | [112] |
| Convergence of characters | [117] |
| Modes of adaptation: Progress | [119] |
| Evolution and Revolution | [120] |
CHAPTER V.
HEREDITY AND THE ORIGIN OF VARIATIONS.
| Heredity in the protozoa | [123] |
| Regeneration of lost parts | [124] |
| Sexual reproduction and heredity | [129] |
| The problem of hen and egg | [130] |
| Reproductive continuity | [131] |
| Pangenesis | [131] |
| Modified pangenesis | [134] |
| Continuity of germ-plasm | [138] |
| Cellular continuity with differentiation | [142] |
| The inheritance or non-inheritance of acquired characters | [146] |
| Origin of variations on the latter view | [149] |
| Hypothesis of organic combination | [150] |
| The extrusion of the second polar cell | [153] |
| The protozoan origin of variations | [156] |
| How can the body influence the germ? | [159] |
| Is there sufficient evidence that it does? | [162] |
| Summary and conclusion | [175] |
CHAPTER VI.
ORGANIC EVOLUTION.